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The terpenes citronellol and citronellal are present in the mandibular glands of Lasius umbratus (Nylander).The alcohol constitutes about 85% of the volatile material in the mandibular gland, whereas the aldehyde is a minor constituent. Citronellal functions as a releaser of alarm for L. umbratus and citronellol is probably employed as a defensive secretion. The gross morphology of the mandibular gland and its reservoir is described. The importance of relative volatility and other factors which may govern the suitability of specific alarm pheromones for ants are discussed.

Three improved xenic diets for raising the Puerto Rico strain of the sugarcane borer, Diatraea saccharalis (F.), resulted in 90% survival from newly-hatched larva to adult. Larval life span was shortened and adult life span was lengthened. The diets are easily prepared with low-cost ingredients and they keep well. Results from these diets are compared with others for this species.

Adult female Anthonomus grandis Boheman became permanently infecund, but males were not affected, when fed various analogues of ecdysone. A trihydroxy, 6-keto steroid was found to be particularly effective and was evaluated extensively as a female chemosterilant. Egg production was suppressed when females fed for only 6 days on diet containing the trihydroxy compound. None of the weevils died, and there was little recovery of fertility High temperatures during treatment and addition of a synergist to the diet favored the sterilizing action. The combined effects of γ-irrardiation and steroid treatment were not completely additive, an indication that the 2 sterilizing agents acted on a common target. Also, the steroid seemed to antagonize the action of the chemosterilant busulfan (1,4-butanediol dimethanesulfonate) when both were given in the diet of the adults. When given in the larval diet, 3 ppm of the trihydroxy steroid lowered the yield of adults, and 10 ppm almost eliminated the formation of adults. Deformities occurred at all stages of development.